• Daipayan Guha, Raphael Jakubovic, Naif M Alotaibi, Jesse M Klostranec, Sidharth Saini, Ryan Deorajh, Shaurya Gupta, Michael G Fehlings, Todd G Mainprize, Albert Yee, and Yang Victor X D VXD Division of Neurosurgery, Department of Surgery, University of Toronto. Toronto, Toronto, Ontario, Canada; Institute of Medical Science, School of Gra.
• Division of Neurosurgery, Department of Surgery, University of Toronto. Toronto, Toronto, Ontario, Canada; Institute of Medical Science, School of Graduate Studies, University of Toronto. Toronto, Toronto, Ontario, Canada; Biophotonics and Bioengineering Laboratory, Sunnybrook Health Sciences Centre. Toronto, Toronto, Ontario, Canada. Electronic address: deep.guha@mail.utoronto.ca.
• World Neurosurg. 2019 May 1; 125: e863-e872.

ObjectiveComputer-assisted three-dimensional navigation often guides spinal instrumentation. Optical topographic imaging (OTI) offers comparable accuracy and significantly faster registration relative to current navigation systems in open posterior thoracolumbar exposures. We validate the usefulness and accuracy of OTI in minimally invasive spinal approaches.MethodsMini-open midline posterior exposures were performed in 4 human cadavers. Square exposures of 25, 30, 35, and 40 mm were registered to preoperative computed tomography imaging. Screw tracts were fashioned using a tracked awl and probe with instrumentation placed. Navigation data were compared with screw positions on postoperative computed tomography imaging, and absolute translational and angular deviations were computed. In vivo validation was performed in 8 patients, with mini-open thoracolumbar exposures and percutaneous placement of navigated instrumentation. Navigated instrumentation was performed in the previously described manner.ResultsFor 37 cadaveric screws, absolute translational errors were (1.79 ± 1.43 mm) and (1.81 ± 1.51 mm) in the axial and sagittal planes, respectively. Absolute angular deviations were (3.81 ± 2.91°) and (3.45 ± 2.82°), respectively (mean ± standard deviation). The number of surface points registered by the navigation system, but not exposure size, correlated positively with the likelihood of successful registration (odds ratio, 1.02; 95% confidence interval, 1.009-1.024; P < 0.001). Fifty-five in vivo thoracolumbar pedicle screws were analyzed. Overall (mean ± standard deviation) axial and sagittal translational errors were (1.79 ± 1.41 mm) and (2.68 ± 2.26 mm), respectively. Axial and sagittal angular errors were (3.63° ± 2.92°) and (4.65° ± 3.36°), respectively. There were no radiographic breaches >2 mm or any neurovascular complications.ConclusionsOTI is a novel navigation technique previously validated for open posterior exposures and in this study has comparable accuracy for mini-open minimally invasive surgery exposures. The likelihood of successful registration is affected more by the geometry of the exposure than by its size.Copyright © 2019 Elsevier Inc. All rights reserved.

33 keywords...

hide…